By using a rigid octadentenate carboxylate linker 5,5′,5″,5″′-silanetetrayltetraisophthalic acid (H8L), three new microporous coordination polymers, namely, [Cu4L(H2O)4]·2DMF·10H2O (1), [Zn5L2(H2O)4][NH2(CH3)2]6·2DMF·4H2O (2), and [Cd3(H2L)2][NH2(CH3)2]6·4DMF·14H2O (3), were solvothermally synthesized and structurally characterized. Compound 1 is a 3D framework built from a square paddlewheel [Cu2(O2CR)4] and a 8-connected cube L ligand to give a (4,8)-connected scu structure. Compound 2 is a 3D 4-nodal (4,4,4,8)-connected network with small 1D channels built on three tetrahedral Zn units and a 8-connecting ligand L. Compound 3 possesses a 3D structure with a (4,4,6)-connected net built on two tetrahedral Cd units and a 6-connecting ligand H2L6–. All the three compounds consist of large solvent accessible voids, but only compound 1 possesses permanent porosity as confirmed by N2, H2, O2, CO2 and CH4 gas adsorption measurements. Compounds 2 and 3 exhibited strong blue fluorescent emissions with a peak at 414 and 412 nm, respectively, at RT upon excitation owing to a ligand-centered excited state.

A novel, efficient and metal-free cascade sulfonylation/cyclization of 2-propynolphenols with commercially available sodium sulfinates was developed for the synthesis of 4-sulfonyl 2H-chromenes under mild conditions.

Based on the ligands tetrakisIJ4-carboxyphenyl)silane (TCS) and 4,4′-bipy, a novel 3D doubly interpenetrated ZnIJII)-paddlewheel metal-organic framework Zn 2 TCSIJ4,4′-bipy) (1) was synthesized via facile conversion of its non-interpenetrated isomer (2) upon solvent removal at ambient temperature. It exhibits high CO 2 and CH 4 adsorption capacities and exceptional water stability.Metal-organic frameworks (MOFs) are a new class of porous materials that have received widespread attention due to their potential applications in gas storage, separation, catalysis, chemical sensors, semiconductors, fuel cells, supercapacitors and more. 1 However, one drawback of MOFs is that most of them are unstable in water and under humid conditions. Generally, MOFs containing tri-or tetravalent metal cations, such as Cr 3+ , Al 3+ , Fe 3+ , Ti 4+ and Zr 4+ , and ZIFs (zeolitic imidazolate frameworks) display a high degree of stability in water. 2-5 We recently calculated the pK a and NBO (Natural Bond Orbital) charges of many ligands applied in MOF synthesis and indicated that these data can be used to predict water stabilities of MOFs. 4 Ligands with higher NBO charges tend to form MOFs with better hydrothermal stability. CrystEngCommThis journal is † Electronic supplementary information (ESI) available: Experimental details, syntheses of 1-3, crystal data for 2 and 3·H 2 O, selected bond distances and angles for 2, PXRD patterns of 1-2, IR spectra of 1, fluorescence and diffuse reflectance UV-vis spectra of 1 and the ligand TCS, and CO 2 sorption isotherms for 1 measured at 298 K. CCDC 1034674, 1056672. For ESI and crystallographic data in CIF or other electronic format see

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